Light emitting diodes (LEDs) can emit light having various colors by using GaAs, AlGaAs, GaN, InGaN, and InGaAlP-based compound semiconductor materials. Such LEDs are packaged to be used as a light source in various fields such as a lightening indicator, a character indicator, and an image indicator.
Such a LED has a structure in which an N-type semiconductor layer, an active layer, and a P-type semiconductor layer are stacked on each other, and light is generated from the active layer and emitted to an exterior if power is applied to the LED.